Vehicle lower part structure

Abstract

To provide a vehicle lower part structure capable of improving cooling performance of a battery.SOLUTION: A vehicle lower part structure 10 comprises: a battery 20 disposed in a lower part of a vehicle V; a cover member 22 that covers the battery 20 from a vehicle lower side; and a ventilation trunk 26 provided between the battery 20 and the cover member 22 so as to enable passing of travel wind and be narrower on a flow path in a discharge part 28 than other parts.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vehicle undercarriage. [Background technology]

[0002] Patent document 1 discloses a battery cooling device that has a structure in which a battery case is arranged under a floor panel, and is provided with a fixing bracket for fixing the battery case to the floor panel, and cools the battery by providing a ventilation passage between the fixing bracket and the bottom surface of the battery case. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-82983 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the battery cooling device described in Patent Document 1 above, the cross-sectional area of ​​the ventilation passage is constant except for the inlet section, so it may not be possible to efficiently take in the wind generated by driving, and there is room for improvement in terms of improving the battery cooling performance.

[0005] An object of the present invention is to provide a vehicle underbody structure that can improve the cooling performance of a battery. [Means for solving the problem]

[0006] The vehicle underbody structure of claim 1 includes a battery disposed under a vehicle, a cover member that covers the battery from the underside of the vehicle, and a ventilation passage between the battery and the cover member that allows wind to pass through while the flow path at the exhaust section is narrower than other portions.

[0007] In the vehicle underbody structure according to claim 1, a battery is disposed under the vehicle and is covered from the vehicle lower side by a cover member. In addition, a ventilation passage is provided between the battery and the cover member. As a result, when the vehicle is traveling, the traveling wind passes through the ventilation passage to cool the battery.

[0008] Furthermore, the air passage has a narrower flow path at the exhaust section than at other portions, which increases the flow rate of air exhausted at the exhaust section and allows more running wind to be introduced into the air passage.

[0009] The vehicle underbody structure of claim 2 is, in claim 1, characterized in that the cover member has a plurality of convex beads extending in the fore-and-aft direction of the vehicle and protruding upwardly of the vehicle, and the ventilation passage is provided between adjacent convex beads in the vehicle width direction.

[0010] In the vehicle underbody structure according to claim 2, the cover member has a plurality of convex beads formed thereon, which increases the rigidity of the cover member. Also, by forming an air passage between adjacent convex beads, it is not necessary to provide a separate dedicated member. Furthermore, since the convex beads protrude upward from the vehicle, interference between the cover member and the road surface can be suppressed compared to a structure formed with a concave bead protruding downward from the vehicle.

[0011] A third aspect of the present invention provides the vehicle underbody structure according to the first aspect, wherein the air passage has a dimension in a vehicle width direction that decreases from the front side of the vehicle to the rear side of the vehicle.

[0012] In the vehicle underbody structure of claim 3, the vehicle width direction dimension of the ventilation passage becomes smaller as it moves from the front side of the vehicle to the rear side of the vehicle, so that the flow rate of air discharged at the exhaust section can be increased without changing the height dimension of the ventilation passage.

[0013] A fourth aspect of the present invention provides the vehicle underbody structure according to the first aspect, wherein the ventilation passage has a dimension in the vehicle up-down direction that decreases from the front side of the vehicle to the rear side of the vehicle.

[0014] In the vehicle underbody structure of claim 4, the dimension of the ventilation passage in the vertical direction of the vehicle decreases as it moves from the front side of the vehicle to the rear side of the vehicle, so that the flow rate of air discharged at the exhaust section can be increased without changing the width dimension of the ventilation passage.

[0015] A fifth aspect of the present invention provides the vehicle underbody structure according to any one of the first to fourth aspects, wherein an inlet of the ventilation passage opens toward the front of the vehicle on a side further forward than the battery.

[0016] In the vehicle underbody structure according to claim 5, the inlet of the ventilation passage is located on the vehicle front side relative to the battery, so that the battery can be cooled up to the front end portion. Also, since the inlet opens toward the vehicle front, it is easy to introduce the wind generated by running. Effect of the Invention

[0017] As described above, according to the vehicle underbody structure of the present invention, the cooling performance of the battery can be improved. [Brief description of the drawings]

[0018] [Figure 1] 1 is a side cross-sectional view that shows, in outline, the overall configuration of a vehicle to which a vehicle underbody structure according to an embodiment is applied. [Diagram 2] FIG. 4 is a plan view of a cover member in the embodiment. [Diagram 3] 3 is a cross-sectional view showing a cross section taken along line 3-3 in FIG. 1. [Figure 4] FIG. 11 is a side cross-sectional view showing a vehicle underbody structure according to a modified example. [Diagram 5] FIG. 11 is a plan view of a cover member in a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] A vehicle underbody structure 10 according to an embodiment will be described with reference to the drawings.

[0020] (Overall configuration of vehicle undercarriage 10) 1 is a side cross-sectional view that shows a schematic overall configuration of a vehicle underbody structure 10 according to an embodiment. The electrode manufacturing apparatus 10 of this embodiment includes a battery 18 disposed under a vehicle V.

[0021] The battery 18 is disposed below a floor panel 12 that constitutes the floor surface of the vehicle compartment. The floor panel 12 is a substantially rectangular plate-shaped member that separates the inside and outside of the vehicle compartment. A front seat 14 and a rear seat 16 are provided on the floor panel 12.

[0022] The battery 18 is accommodated in a battery case 18. In this embodiment, as an example, the battery case 18 is configured to include an upper case 18A and a lower case 18B. The lower case 18B is formed in a substantially rectangular plate shape extending in the vehicle front-rear direction and the vehicle width direction, and the battery 18 is disposed on the upper surface of the lower case 18B. In addition, an outer peripheral end of the lower case 18B is curved upward, and a flange portion further extends outward.

[0023] The upper case 18A is formed in a generally rectangular plate shape extending in the vehicle front-rear direction and the vehicle width direction, similar to the lower case 18B. A flange portion is formed on the outer peripheral end of the upper case 18A to be overlapped with a flange portion of the lower case 18B. The flange portions are mechanically fastened to each other by bolts or the like to form the battery case 18.

[0024] A cover member 22 that covers the battery 18 (battery case 18) from the vehicle lower side is provided below the battery case 18. The cover member 22 may be, for example, an undercover that covers the vehicle body from the vehicle lower side.

[0025] Fig. 2 is a plan view of the cover member 22 in the embodiment. As shown in Fig. 2, the cover member 22 is formed of a metal plate having a substantially rectangular shape extending in the vehicle front-rear direction and the vehicle width direction. Here, as an example, in the present embodiment, the battery 18 is disposed below the floor panel 12 over the entire area in the vehicle width direction, and the cover member 22 is formed to a size capable of covering the entire battery 18 from the vehicle lower side.

[0026] Further, a plurality of convex beads extending in the vehicle front-rear direction and protruding upward of the vehicle are formed on the cover member 22. In the present embodiment, as an example, the cover member 22 is formed with a first convex bead 22A, a second convex bead 22B, and a third convex bead 22C.

[0027] The first convex bead 22A is formed in the center of the cover member 22 in the vehicle width direction, and extends in the vehicle front-rear direction. In addition, second convex beads 22B are formed on both sides of the first convex bead 22A in the vehicle width direction with a gap therebetween. That is, a pair of second convex beads 22B are formed on the left and right of the first convex bead 22A.

[0028] Here, the second convex bead 22B extends in the vehicle front-rear direction substantially parallel to the first convex bead 22A except for the rear portion. The rear portion of the second convex bead 22B is inclined inward in the vehicle width direction so as to approach the first convex bead 22A from the vehicle front side to the vehicle rear side. Therefore, the distance between the first convex bead 22A and the second convex bead 22B narrows from the vehicle front side to the vehicle rear side.

[0029] A third convex bead 22C is formed on the outer side in the vehicle width direction of the second convex bead 22B. The third convex bead 22C is formed on the outer side in the vehicle width direction of the rear part of the second convex bead 22B, and is shorter than the first convex bead 22A and the second convex bead 22B. The third convex bead 22C is inclined inward in the vehicle width direction so as to approach the second convex bead 22B from the front side to the rear side of the vehicle.

[0030] The first convex bead 22A, the second convex bead 22B, and the third convex bead 22C each protrude upward toward the vehicle, and a ventilation passage 26 is provided between adjacent convex beads in the vehicle width direction. That is, the ventilation passage 26 is provided between the first convex bead 22A and the second convex bead 22B. Similarly, the ventilation passage 26 is provided between the second convex bead 22B and the third convex bead 22C. Therefore, the dimension of the ventilation passage 26 in the vehicle width direction becomes smaller from the vehicle front side to the vehicle rear side. In other words, the flow path in the discharge portion 28 set at the rear end of the ventilation passage 26 is narrower than other portions.

[0031] Fig. 3 is a cross-sectional view showing a cross section cut along line 3-3 in Fig. 1. As shown in Fig. 3, in this embodiment, as an example, an end of the battery 18 in the vehicle width direction is fastened to a rocker 30 which is a framework member.

[0032] The rocker 30 is a frame member with a closed cross section extending in the vehicle front-rear direction, and includes a rocker inner panel 32 on the inside in the vehicle width direction, and a rocker outer panel 34 on the outside in the vehicle width direction. The rocker inner panel 32 is formed in a generally hat-shaped cross section with the outside in the vehicle width direction open, and a flange extends in the vehicle up-down direction.

[0033] The rocker outer panel 34 is formed in a generally hat-shaped cross section with an open inner side in the vehicle width direction, and a flange is formed at a position corresponding to the flange of the rocker inner panel 32. The flange of the rocker inner panel 32 and the flange of the rocker outer panel 34 are joined by spot welding or the like in an overlapping state. The rocker 30 may be integrally formed by extrusion molding of an aluminum alloy or the like.

[0034] Bolt insertion holes (not shown) are formed in the vehicle width direction ends of the battery case 18, and bolts 38 are inserted into the bolt insertion holes and screwed into weld nuts 40 provided on the rocker inner panel 32. A spacer 36 is provided between the rocker inner panel 32 and the battery case 18.

[0035] The cover member 22 has its vehicle width direction end bent toward the vehicle upper side, and extends along the lower case 18B of the battery case 18. In addition, a first convex bead 22A and a second convex bead 22B formed on the cover member 22 are fastened to the lower case 18B by bolts 42, respectively.

[0036] Specifically, a bolt hole is formed in the first convex bead 22A and the second convex bead 22B, and the bolt 42 is inserted into the bolt hole from the vehicle lower side. Therefore, the head of the bolt 42 fits into the recess formed by the first convex bead 22A and the recess formed by the second convex bead 22B, respectively.

[0037] The bolt 42 is screwed into a weld nut 44 provided on the lower case 18B of the battery case 18. In addition, a spacer 46 is provided between the first convex bead 22A and the lower case 18B, and between the second convex bead 22B and the lower case 18B.

[0038] In this way, a gap is provided between the battery case 18 and the cover member 22, and this gap serves as a ventilation passage 26 through which the wind generated during running can pass. As shown in Fig. 1, the inlet of the ventilation passage 26 opens toward the front of the vehicle and on the vehicle front side relative to the battery 20.

[0039] (action) Next, the operation of the vehicle underbody structure 10 according to this embodiment will be described.

[0040] In the vehicle underbody structure 10 according to this embodiment, a battery 20 is disposed under the vehicle V, and the battery 20 is covered from the vehicle lower side by a cover member 22. In addition, a ventilation passage 26 is provided between the battery 20 and the cover member 22. As a result, when the vehicle V is traveling, the traveling wind passes through the ventilation passage 26, thereby cooling the battery 20.

[0041] In particular, in this embodiment, the inlet of the ventilation passage 26 is located further forward of the battery 20, so that it is possible to cool the battery up to the front end of the battery 20. Also, since the inlet opens toward the front of the vehicle, it is easier to introduce the running wind compared to a structure that introduces the running wind from below the vehicle body.

[0042] 2, in this embodiment, the cross-sectional area of ​​the exhaust portion 28 of the ventilation passage 26 is smaller than that of other portions. This increases the flow rate of air exhausted at the exhaust portion 28, making it possible to introduce more running wind into the ventilation passage 26. In particular, in this embodiment, the dimension of the ventilation passage 26 in the vehicle width direction decreases from the front side of the vehicle to the rear side of the vehicle, so that the flow rate of air exhausted at the exhaust portion 28 can be increased without changing the height dimension of the ventilation passage 26.

[0043] Furthermore, in this embodiment, since a plurality of convex beads 22A, 22B, and 22C are formed on the cover member 22, it is possible to increase the rigidity of the cover member 22. Also, by forming the spaces between the adjacent convex beads as the ventilation passages 26, it is not necessary to provide a separate dedicated member.

[0044] Furthermore, in this embodiment, the first convex bead 22A, the second convex bead 22B, and the third convex bead 22C protrude upward from the vehicle, and therefore interference between the cover member 22 and the road surface can be suppressed compared to a structure in which a concave bead protruding downward from the vehicle is formed. That is, if a concave bead is formed on the cover member 22, the concave bead protrudes downward from the general portion of the cover member 22, and therefore it may not be possible to secure a gap between the cover member 22 and the road surface. In addition, if the cover member 22 is moved upward from the vehicle to secure a gap between the cover member 22 and the road surface, the mounting space for the battery 20 and the interior space of the vehicle may become narrow. In contrast, in this embodiment, only the convex bead protruding upward from the vehicle is formed on the cover member 22, and therefore it is possible to suppress the cushioning between the cover member 22 and the road surface while securing the interior space of the vehicle and the mounting space for the battery 20.

[0045] In this embodiment, the gap between the battery case 18 and the cover member 22 is substantially the same from the front to the rear as shown in Fig. 1, but is not limited to this. For example, the modified structure shown in Fig. 4 and Fig. 5 may be adopted.

[0046] (Modification) Fig. 4 is a side cross-sectional view showing a vehicle underbody structure 10 according to a modified example. Fig. 5 is a plan view of a cover member 22 in the modified example. As shown in Fig. 4, the modified example is different in structure from the embodiment in that the cover member 22 is inclined in side view.

[0047] Specifically, a cover member 22 is provided below the battery case 18, and the cover member 22 is inclined so as to be positioned higher from the front side of the vehicle to the rear side of the vehicle. Therefore, the dimension of the ventilation passage 26 between the battery case 18 and the cover member 22 in the vertical direction of the vehicle becomes smaller from the front side of the vehicle to the rear side of the vehicle.

[0048] 5, a first convex bead 22A, a second convex bead 22B, and a third convex bead 22C are formed on the cover member 22. The first convex bead 22A is formed in the center portion of the cover member 22 in the vehicle width direction, and extends in the vehicle front-rear direction.

[0049] The second convex beads 22B are formed on both sides of the first convex bead 22A in the vehicle width direction, and extend in the vehicle front-rear direction substantially parallel to the first convex bead 22A. Therefore, the ventilation passage 26 between the first convex bead 22A and the second convex bead 22B has substantially the same width from the inlet at the front to the exhaust part 28 at the rear.

[0050] In this modified example, the dimension of the ventilation passage 26 in the vehicle width direction does not change, but the dimension of the ventilation passage 26 in the vehicle vertical direction decreases as one moves from the front side of the vehicle to the rear side of the vehicle. As a result, as in the embodiment, the flow rate of air discharged at the exhaust section 28 increases, and more driving wind can be introduced into the ventilation passage 26.

[0051] In this modification, the dimensions of the ventilation passage 26 in the vehicle width direction may be decreased from the front side of the vehicle to the rear side of the vehicle as shown in Fig. 2. In this case, the dimensions of the ventilation passage 26 in the vehicle up-down direction and the vehicle width direction decrease from the front side of the vehicle to the rear side of the vehicle, so that the flow velocity in the discharge portion 28 becomes larger, and the cooling performance of the battery 20 can be improved.

[0052] Although the vehicle underbody structure 10 according to the present invention has been described above, it is needless to say that the present invention can be embodied in various forms without departing from the gist of the present invention. In the above embodiment, as shown in FIG. 2, the first convex bead 22A, the second convex bead 22B, and the third convex bead 22C are formed on the cover member 22, and the ventilation passage 26 is provided between the adjacent convex beads, but the present invention is not limited to this. For example, the cover member 22 may have a structure in which the convex bead is not formed. Even in this case, if the cross-sectional area of ​​the exhaust portion 28 in the ventilation passage 26 is made smaller than the other portions, the cooling performance of the battery 20 can be improved as in the above embodiment. As a method for reducing the cross-sectional area of ​​the ventilation passage 26, there is a method of inclining the cover member 22 as shown in FIG. 4. In addition, as another method, there is a method of providing a convex bead on the battery case 18 without providing a convex bead on the cover member 22. That is, a convex bead protruding from the lower case 18B of the battery case 18 toward the cover member 22 may be formed, and the ventilation passage may be provided between the convex beads.

[0053] In the above embodiment, as shown in FIG. 3, the first convex bead 22A and the second convex bead 22B of the cover member 22 are fastened to the battery case 18 by the bolts 42, but the present invention is not limited to this. For example, the general portion of the cover member 22 and the battery case 18 may be mechanically fastened by bolts or the like. Also, the portions of the cover member 22 extending from both ends in the vehicle width direction to the upper side of the vehicle may be mechanically fastened to the lower case 18B. Furthermore, both ends in the vehicle width direction of the cover member 22 may be curved along the lower case 18B and overlapped with the lower surface of the flange of the lower case 18B, and the cover member 22 together with the upper case 18A and the lower case 18B may be fastened to the rocker 30 by the bolts 38.

[0054] Regarding the above embodiment, the following notes are disclosed. (Appendix 1) A battery disposed under the vehicle; A cover member that covers the battery from a lower side of the vehicle; A ventilation passage is provided between the battery and the cover member to allow a traveling wind to pass therethrough, and a cross-sectional area of ​​an exhaust portion is smaller than that of other portions; A vehicle undercarriage having a (Appendix 2) The cover member is formed with a plurality of convex beads extending in the vehicle front-rear direction and protruding upwardly of the vehicle, 2. The vehicle underbody structure according to claim 1, wherein the ventilation passage is provided between the convex beads adjacent to each other in the vehicle width direction. (Appendix 3) 3. The vehicle underbody structure according to claim 1, wherein the ventilation passage has a widthwise dimension that decreases from the front side of the vehicle to the rear side of the vehicle. (Appendix 4) 3. The vehicle underbody structure according to claim 1, wherein the ventilation passage has a dimension in a vertical direction of the vehicle that decreases from a front side of the vehicle to a rear side of the vehicle. (Appendix 5) 5. The vehicle underbody structure according to claim 1, wherein the inlet of the ventilation passage opens toward the front of the vehicle and further forward than the battery. [Explanation of symbols]

[0055] 10 Vehicle underbody structure 20 Battery 22 Cover member 22A 1st convex bead 22B 2nd convex bead 22C 3rd convex bead 26 Ventilation duct 28 Discharge section V Vehicle

Claims

1. A battery disposed under the vehicle; A cover member that covers the battery from a lower side of the vehicle; A ventilation passage is provided between the battery and the cover member to allow a traveling wind to pass therethrough, and the flow path in the exhaust portion is narrower than other portions; A vehicle undercarriage having a

2. The cover member is formed with a plurality of convex beads extending in the vehicle front-rear direction and protruding upwardly of the vehicle, The vehicle underbody structure according to claim 1 , wherein the ventilation passage is provided between the convex beads adjacent to each other in a vehicle width direction.

3. The vehicle underbody structure according to claim 1 , wherein the ventilation passage has a dimension in a vehicle width direction that decreases from a front side to a rear side of the vehicle.

4. The vehicle underbody structure according to claim 1 , wherein the ventilation passage has a dimension in a vertical direction of the vehicle that decreases from a front side of the vehicle to a rear side of the vehicle.

5. The vehicle underbody structure according to any one of claims 1 to 4, wherein the inlet of the ventilation passage is open toward the front of the vehicle and on a front side of the vehicle relative to the battery.

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